San Francisco planners have approved plans to build what will become the city's tallest building.

Thursday's decision by the Planning Commission clears the way for funding and construction of the 61-story Transbay Tower.

Planners say the 1,070-foot-tall building at 101 First Street will become the centerpiece of the downtown skyline. It will be 217 feet taller than the 853-foot-tall Transamerica Pyramid.

The new office tower will be part of the planned Transit Center District that will include commercial high-rises, residential buildings, hotels and retail space, as well as bus and train lines.

Some residents have expressed concerns about the buildings' sizes and increase in people downtown, but officials say the mega-towers will help meet the city's needs for office space and residential units.